Wednesday, November 14, 2018

Recent Research on Wireless Radiation and Electromagnetic Fields

I have been circulating abstracts of newly-published scientific papers on wireless radiation and electromagnetic fields (EMF) about once or twice a month since August, 2016. These updates are sent to several hundred EMF scientists around the world.

The complete collection of abstracts including the latest additions which appear below now covers more than 500 scientific papers. The collection can be downloaded by clicking on the following link:

Note: This link will change when new abstracts are added to the compilation.

See EMF-Portalfor a searchable database of EMF studies. The Portal contains over 26,000 publications and 6,000 summaries of scientific studies on the effects of EMF. The Portal is a project of RWTH University Hospital in Aachen, Germany.

Latest Additions

Cell phone use and risk of thyroid cancer: a population-based case-control study in Connecticut

Purpose This study aims to investigate the association between cell phone use and thyroid cancer.

Methods A population-based case-control study was conducted in Connecticut between 2010 and 2011 including 462 histologically confirmed thyroid cancer cases and 498 population-based controls. Multivariate unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI) for associations between cell phone use and thyroid cancer.

Results Cell phone use was not associated with thyroid cancer (OR: 1.05, 95% CI: 0.74-1.48). A suggestive increase in risk of thyroid microcarcinoma (tumor size ≤10mm) was observed for long-term and more frequent users. Compared to cell phone non-users, several groups had non-statistically significantly increased risk of thyroid microcarcinoma: individuals who had used a cell phone >15 years (OR: 1.29, 95% CI: 0.83-2.00), who had used a cell phone >2 hours per day (OR: 1.40, 95% CI: 0.83-2.35), who had the most cumulative use hours (OR: 1.58, 95% CI: 0.98-2.54), and who had the most cumulative calls (OR: 1.20, 95% CI: 0.78-1.84).

Conclusion This study found no significant association between cell phone use and thyroid cancer. A suggestive elevated risk of thyroid microcarcinoma associated with long-term and more frequent uses warrants further investigation.

Hardell L, Carlberg M. Comments on the US National Toxicology Program technical reports on toxicology and carcinogenesis study in rats exposed to whole-body radiofrequency radiation at 900 MHz and in mice exposed to whole-body radiofrequency radiation at 1,900 MHz. International Journal of Oncology. Published Oct 24, 2018. https://doi.org/10.3892/ijo.2018.4606

Abstract

During the use of handheld mobile and cordless phones, the brain is the main target of radiofrequency (RF) radiation. An increased risk of developing glioma and acoustic neuroma has been found in human epidemiological studies. Primarily based on these findings, the International Agency for Research on Cancer (IARC) at the World Health Organization (WHO) classified in May, 2011 RF radiation at the frequency range of 30 kHz‑300 GHz as a ‘possible’ human carcinogen, Group 2B. A carcinogenic potential for RF radiation in animal studies was already published in 1982. This has been confirmed over the years, more recently in the Ramazzini Institute rat study. An increased incidence of glioma in the brain and malignant schwannoma in the heart was found in the US National Toxicology Program (NTP) study on rats and mice. The NTP final report is to be published; however, the extended reports are published on the internet for evaluation and are reviewed herein in more detail in relation to human epidemiological studies. Thus, the main aim of this study was to compare earlier human epidemiological studies with NTP findings, including a short review of animal studies. We conclude that there is clear evidence that RF radiation is a human carcinogen, causing glioma and vestibular schwannoma (acoustic neuroma). There is some evidence of an increased risk of developing thyroid cancer, and clear evidence that RF radiation is a multi‑site carcinogen. Based on the Preamble to the IARC Monographs, RF radiation should be classified as carcinogenic to humans, Group 1.

de Vocht F. Analyses of temporal and spatial patterns of Glioblastoma Multiforme and other brain cancers subtypes in relation to mobile phones using synthetic counterfactuals. Environmental Research. Available online 17 October 2018. https://doi.org/10.1016/j.envres.2018.10.011.

Highlights

• English 1985–2005 brain cancer subtype rates were compared to counterfactual trends• Excess GBM increases were found in the frontal and temporal lobes, and cerebellum• Mobile phone use was unlikely to have been an important putative factor• No evidence of an effect of mobile phone use on acoustic neuroma and meningioma

Abstract

This study assesses whether temporal trends in glioblastoma multiforme (GBM) in different brain regions, and of different malignant and benign (including acoustic neuroma and meningioma) subtypes in the temporal lobe, could be associated with mobile phone use.

Annual 1985–2005 incidence of brain cancer subtypes for England were linked to population-level covariates. Bayesian structural timeseries were used to create 2006–2014 counterfactual trends, and differences with measured newly diagnosed cases were interpreted as causal effects.

Increases in excess of the counterfactuals for GBM were found in the temporal (+38% [95% Credible Interval -7%,78%]) and frontal (+36% [-8%,77%]) lobes, which were in agreement with hypothesised temporal and spatial mechanisms of mobile phone usage, and cerebellum (+59% [-0%,120%]). However, effects were primarily present in older age groups, with largest effects in 75+ and 85+ groups, indicating mobile phone use is unlikely to have been an important putative factor. There was no evidence of an effect of mobile phone use on incidence of acoustic neuroma and meningioma.

Although 1985–2014 trends in GBM in the temporal and frontal lobes, and probably cerebellum, seem consistent with mobile phone use as an important putative factor, age-group specific analyses indicate that it is unlikely that this correlation is causal.

Excerpts

Assessment of specific cancer subtypes in the temporal lobe indicated that the excess incidence was mainly found for GBM, with similar trends observed in the frontal lobe and cerebellum.... The increased rates of specific brain cancer subtypes in excess of the counterfactuals correspond to the spatial and temporal patterns that would be expected if exposure to RF from mobile phones were an important putative factor (Cardis et al., 2008, Morgan et al., 2016) ... However, age group-specific analyses indicate that the excess relative impacts increased with age over 65 years and were primarily found in the very old (75/85+ years of age) for whom it is unlikely that mobile phone use had been an important causal factor. In addition, excess numbers of newly diagnosed cases were also observed in the young (<24 years of age) for whom mobile phone use is also an unlikely causal factor....

The assumption that a 10-year lag was the most plausible period between first exposure and when increased risk could be observed in registry data was based on the previous analyses (De Vocht (2016)). Although sensitivity analysis using a 15-year lag showed no evidence of excesses relative to counterfactuals, this may still have been too short....

This study, in agreement with other data from the UK and elsewhere, shows that the incidence of glioblastoma multiforme (astrocytoma grade IV) has increased significantly since the 1980s, especially in the frontal and temporal lobes and cerebellum. However, it further provides evidence that the trend of increasing numbers of newly diagnosed cases of glioblastoma multiforme in the temporal lobe (but likely in the frontal lobe and cerebellum as well) since the mid-1980s, although seemingly consistent with the hypothesis of exposure to radiofrequency radiation from mobile phones being an important putative factor, should to a large extent (if not exclusively) be attributed to another factor or factors; of which improvements in diagnostic techniques, especially in the elderly, seems the most plausible. Although these analyses indicate that it is unlikely that exposure to RF from mobile phones is an important putative factor, they also cannot exclude it as a contributing factor completely. It is therefore important to keep monitoring incidence trend data.

Competing financial interests declaration: The author has previously done consulting for EPRI [Electric Power Research Institute], not related to this work. Financial support: No external funding was obtained for this study.

My comment: The study found that the two age groups most vulnerable to carcinogenic effects from cell phone use -- young and elderly adults -- showed increased incidence over time in brain cancer in two lobes of the brain that receive the greatest dose of microwave radiation from a cell phone used near the head. The author rejects the explanation that cell phone use caused the increased cancer risk but accepts the possibility that cell phone radiation may be a contributing factor.

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RF EMF, screen time, and emotional and behavioral problems in 5-year-old children

Highlights• RF-EMF from different sources and screen time assessed in 5-year-old children.• Teachers and mothers independently reported child emotional and behavioural problems.• No associations with mobile/cordless phone calls which lead to peak RF-EMF to the head.• Associations with exposures contributing very little to RF-EMF when maternal-reported.

Abstract

BACKGROUND: Little is known about the exposure of young children to radiofrequency electromagnetic fields (RF-EMF) and potentially associated health effects. We assessed the relationship of RF-EMF exposure from different sources and screen time exposure with emotional and behavioural problems in 5-year-old children.

METHODS: Cross-sectional study including 3102 children aged 5 years from the Amsterdam Born Children and their Development (ABCD) study, in the Netherlands. Residential RF-EMF exposure from mobile phone base stations was estimated with a 3D geospatial radio wave propagation model. Residential presence of RF-EMF indoor sources (cordless phone base stations and Wireless Fidelity (WiFi)), children's mobile phone and cordless phone calls and screen time exposure (computer/video game and television watching) was reported by the mother. Teachers (n = 2617) and mothers (n = 3019) independently reported child emotional and behavioural problems using the Strengths and Difficulties Questionnaire.

CONCLUSION: Mobile phone and cordless phone calls, which lead to peak RF-EMF exposures to the head, were not associated with any emotional and behavioural problems in 5-year-old children. Environmental RF-EMF exposure from mobile phone base stations and from indoor sources and television watching, which both contribute very little to RF-EMF exposure, were associated with specific emotional and behavioural problems but mainly when reported by the mothers. We cannot, however, discard residual confounding or reverse causality. Further longitudinal research in particular as children will increase the use of telecommunication devices with the age may help to better understand the exact contribution of the different RF-EMF exposure sources if any. Moreover, a thorough control for confounding is essential for a correct interpretation of the studies on screen time and emotional and behavioural problems.

This perspective presents empirical data to demonstrate the existence of different expert views on scientific policy advice on complex environmental health issues. These views are partly research-field specific. According to scientific literature, experts differ in the way they provide policy advice on complex issues such as electromagnetic fields (EMF), particulate matter (PM), and antimicrobial resistance (AMR). Where some experts feel their primary task is to carry out fundamental research, others actively engage in the policy dialogue. Although the literature provides ideas about expert roles, there exists little empirical underpinning. Our aim is to gather empirical evidence about expert roles. The results of an international study indicated that experts on EMF, PM, and AMR differ in the way they view their role in the policy dialogue. For example, experts differed in their views on the need for precaution and their motivation to initiate stakeholder cooperation. Besides, most experts thought that their views on the risks of EMF/PM/AMR did not differ from those of colleagues. Great dissensus was found in views on the best ways of managing risks and uncertainties. In conclusion, the theoretical ideal-typical roles from the literature can be identified to a certain extent.

The principal component analysis (PCA) resulted in six factors, which we interpreted as representing the following six roles: (1) engaged scientist, (2) pro‐science expert, (3) regulatory advocate, (4) humble scientist, (5) transparent expert, and (6) issue advocate. Engaged scientists highly valued scientific knowledge and stressed the importance of a continuous dialogue between scientists and policymakers. Pro‐science experts strongly agreed that new policies should be based on scientific knowledge, that knowledge possessed by the general public is less valuable, and that monitoring is the most suitable way to address the risks and uncertainties of EMF/PM. Regulatory advocates strongly agreed that possible health problems are best managed through legislation and regulation, that scientists should publish in peer‐reviewed journals as their primary responsibility, and that they are not responsible for maintaining a continuous dialogue with policymakers. Humble scientists strongly agreed that scientists should be humble about the role of science in solving societal problems and had modest judgments regarding most other statements. Transparent experts emphasized the importance of transparency regarding research methods and assumptions, explicating differences of opinion among experts, and informing policymakers about the science underlying policy advice. Finally, issue advocates focused on actively interacting with policymakers and politics; they were fairly neutral in regard to the policy measures that should be taken.

There have been numerous published studies reporting on the extent of genetic damage observed in animal and human cells exposed in vitro and in vivo to non-ionizing radiofrequency fields (RF, electromagnetic waves that carry energy as they propagate in air and dense media). Overall, the data are inconsistent; while some studies have suggested significantly increased damage in cells exposed to RF energy compared to unexposed and/or sham-exposed control cells, others have not. Several variables in exposure conditions used in the experiments might have contributed to the controversy.

In this comprehensive review, four specific quality control measures were used to determine the quality of 225 published studies in animal and human cells exposed in vitro and in vivo to RF energy, and the results from 2,160 tests with different sample sizes were analyzed. The four specific quality control measures were as follows: 1. "Blind" collection/analysis of the data to eliminate individual/observer "bias"; 2. Adequate description of "dosimetry" for independent replication/confirmation; 3. Inclusion of "positive controls" to confirm the outcomes; and 4. Inclusion of "sham-exposed controls" which are more appropriate to compare the data with those in RF exposure conditions. In addition, meta-analysis of the genetic damage in cells exposed to RF energy and control cells, thus far available in the RF literature database, was performed to obtain the "d" values, i.e., standardized mean difference between these two types of cells or the effect size. The relationship between d values and the above-mentioned quality control measures was ascertained. In addition, the correlation between the quality control measures and the conclusions reported in the publications (no significant difference between the cells exposed to RF energy and control cells; increased damage in former cells compared to the latter; increased, no significant difference and decreased damage in cells exposed to RF energy in the same experiment; or decreased damage in cells exposed to RF energy) was examined.

The overall conclusions were as follows: 1. When all four quality control measures were mentioned in the publication, the d values were smaller compared to those when one or more quality control measures were not mentioned in the investigation; 2. Based on the inclusion of quality control measures, the weighted outcome in cells exposed to RF energy (d values) indicated a very small effect, if any; 3. The number of published studies reporting no significant difference in genetic damage of cells exposed to RF energy, compared to that of control cells, increased with increased number of quality control measures employed in investigations; 4. The number of published studies reporting increased genetic damage in cells exposed to RF energy decreased with increased number of quality control measures; and 5. There was a "bias" towards the publications reporting increased genetic damage in cells exposed to RF energy even with very small sample size. Overall, the results from this study underscore the importance of including quality control measures in investigations so that the resulting data are useful, nationally and internationally, in evaluating "potential" health risks from exposure to RF energy.

PURPOSE:This topic review aims to explain the mechanism of low-level microwave (MW) radiation effect based on published research results. The review presents the analysis of theoretical and experimental results comprising underlying physics and derived biological-physiological consequences supported by experimental data.

CONCLUSIONS: The rotation of dipolar molecules causes polarization of dielectric medium and restructuring of hydrogen bonds between these molecules. The weakened hydrogen bonds decrease viscosity and enhance diffusion at constant temperature. All steps of proposed model have no critical frequency restrictions at MW frequencies and have been confirmed by electromagnetic field (EMF) theory and/or published experimental results. The synchronous cumulative impact of coherent MW electric field makes possible the field-induced effect despite the field strengths are much weaker than intermolecular fields. The rotation of dipolar molecules results in restructuring hydrogen bonds between the molecules despite the energy of MW radiation is much less than the energy of bonding. The cumulative impact of coherent MW field in a medium has been convincingly confirmed by the measurable dielectric permittivity of the medium. The described mechanism of MW field-induced effect confirms that the nature of the effect differs from the thermal effect and that the exposure by MW radiation can create the specific consequences in biology and materials not characteristic for conventional heating.

IEEE802.15.4g is a low-power wireless standard initially designed for Smart Utility Networks, i.e., for connecting smart meters. IEEE802.15.4g operates at sub-GHz frequencies to offer 2⁻3× longer communication range compared to its 2.4 GHz counterpart. Although the standard offers 3 PHYs (Frequncy Shift Keying, Orthogonal Frequency Division Multiplexing and Offset-Quadrature Phase Shift Keying) with numerous configurations, 2-FSK at 50 kbps is the mandatory and most prevalent radio setting used. This article looks at whether IEEE802.15.4g can be used to provide connectivity for outdoor deployments. We conduct range measurements using the totality of the standard (all modulations with all further parametrization) in the 863⁻870 MHz band, within four scenarios which we believe cover most low-power wireless outdoor applications: line of sight, smart agriculture, urban canyon, and smart metering. We show that there are radio settings that outperform the "2-FSK at 50 kbps" base setting in terms of range, throughput and reliability. Results show that highly reliable communications with data rates up to 800 kbps can be achieved in urban environments at 540 m between nodes, and the longest useful radio link is obtained at 779 m. We discuss how IEEE802.15.4g can be used for outdoor operation, and reduce the number of repeater nodes that need to be placed compared to a 2.4 GHz solution.

The nervous system is an important target of radiofrequency (RF) radiation exposure since it is the excitable component that is potentially able to interact with electromagnetic fields. The present study was designed to investigate the effects of 1,800 MHz RF radiation and the protective role of paricalcitol on the rat sciatic nerve. Rats were divided into four groups as control, paricalcitol, RF, and RF + paricalcitol. In RF groups, the rats were exposed to 1,800 MHz RF for 1 h per day for 4 weeks. Control and paricalcitol rats were kept under the same conditions without RF application. In paricalcitol groups, the rats were given 0.2 μg/kg/day paricalcitol, three times per week for 4 weeks. Amplitude and latency of nerve compound action potentials, catalase activities, malondialdehyde (MDA) levels, and ultrastructural changes of sciatic nerve were evaluated. In the RF group, a significant reduction in amplitude, prolongation in latency, an increase in the MDA level, and an increase in catalase activity and degeneration in the myelinated nerve fibers were observed. The electrophysiological and histological findings were consistent with neuropathy, and the neuropathic changes were partially ameliorated with paricalcitol administration.

The effects of 900–1,800 MHz RF on the nervous system have been investigated in different studies. In these studies, it was shown that exposure to RF radiation may cause changes in amygdala morphology and emotional behavior [Narayanan et al., 2018] and changes in cerebral cortex neurotransmitter release [Kim et al., 2017]. In addition, it has been reported that RF radiation may lead to cytotoxicity in hippocampal neuronal HT22 cells [Kim et al., 2017] and degenerative changes in hippocampus pyramidal cells [Hussein et al., 2016]. In a recent study, evidence was provided showing an association between mobile phone use and brain tumors, especially in people who used their mobile phones for more than 10 years [Prasad et al., 2017]. In another study, it was reported that long‐term use of mobile phones was linked to an increased risk of intracranial tumors [Bortkiewicz et al., 2017]. These studies show that the nervous systems of both humans and animals are sensitive to RF. However, there are studies in the literature that suggest that exposure to RF radiation does not cause any adverse health effects [Chapman et al., 2016; Mohan et al., 2016; Sato et al., 2017].

A whole‐body average E‐field value was calculated from these electric field values. Average E‐field was 6.05 ± 0.67 V/m. This measured E‐field value was used in an electromagnetic field solver to find the electric field distribution and to calculate SAR....

The distribution of E field and SAR are given in Figure A and B, respectively. As seen from Figure B, the maximum SAR (10 g) is 0.00421 W/kg.

In the present study, the effects of 1800 MHz RF radiation on the sciatic nerve were investigated electrophysiologically, biochemically, and histologically. Our findings showed that 1,800 MHz RF radiation could cause neuropathic changes by inducing oxidative stress. Neuropathic damage was partially improved with 0.2 μg/kg/day paricalcitol, non‐hypercalcemic vitamin D analog. However, further studies should be performed by applying different doses to determine the most effective dose of paricalcitol.

BACKGROUND: Electromagnetic fields (EMF) created by mobile phones during communication have harmful effects on different organs.

OBJECTIVES: To explore the effects of exposure to EMF of mobile phones for different durations on hematological parameters and serum hepcidin in male albino rats.

METHODS: Three groups of eight rats: Sham group: rats were exposed to a mobile phone while it was switched off, Experimental group I: rats were exposed to microwave radiation from a mobile phone at 9 am for 30 min. Experimental group II: rats were exposed to microwave radiations from a mobile phone at 9 am for an hour. In all groups, the exposure was conducted daily for a total period of 5 months, followed by estimation of serum hepcidin, total leukocyte count (TLC), interleukin 6 (IL6), serum iron, serum ferritin, plasma hemoglobin (Hb), hematocrit value (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC) and 1.25 dihydroxycholecalciferol levels.

RESULTS: In Experimental group II, there was a significant increase in serum hepcidin, TLC, IL6 and serum ferritin; however, serum iron, TIBC, UIBC, 1.25 dihydroxycholecalciferol, plasma Hb, Hct, MCV and MCH were significantly lower in comparison to sham-exposed group. In Experimental group I, there was a significant increase in serum hepcidin, IL6 and TLC, along with non-significant changes in the remaining studied parameters in comparison to the sham-exposed group.

CONCLUSION: Chronic exposure to EMF from mobile phones increases hepcidin level with subsequent impairment of iron parameters, in addition to negatively affecting both UIBC and TIBC.

Materials and Methods: Human kidney healthy cells in three groups were placed into three batches. The first and second groups (exposed groups) were exposed to a mobile phonesimulator for 1 and 2 h/d, respectively. The irradiation was performed for 8 consecutive days. For the third group (control group), no radiation was applied to the samples and they completed the assay cycle under identical conditions. Cells' survival was evaluated using MTT [3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide] assay. Statistical significance of the differences between control and exposed groups were assessed using the repeated measure ANOVA method (P < 0.05).

Results: Results showed that radiation exposure from mobile phones simulator decreased the kidney cell survival in the exposed groups (up to 40%). ANOVA test revealed that a significant decrease in cell survival in the exposed group compared to the control group (P = 0.014). No significant differences between the irradiated groups were found (P > 0.05).

Conclusion: Mobile phone exposure affects kidney cells survival during an in vitro condition. To study the effects of mobile phoneradiation on kidney, further in vivo studies on mammalians are needed.

Portable devices measuring radiofrequency electromagnetic fields (RF‐EMF) are affected by crosstalk: signals originating in one frequency band that are unintentionally registered in another. If this is not corrected, total exposure to RF‐EMF is biased, particularly affecting closely spaced frequency bands such as GSM 1800 downlink (1,805–1,880 MHz), DECT (1,880–1,900 MHz), and UMTS uplink (1,920–1,980 MHz). This study presents an approach to detect and correct crosstalk in RF‐EMF measurements, taking into account the real‐life setting in which crosstalk is intermittently present, depending on the exact frequency of the signal. Personal measurements from 115 volunteers from Zurich canton, Switzerland were analyzed. Crosstalk‐affected observations were identified by correlation analysis, and replaced by the median value of the unaffected observations, measured during the same activity. DECT is frequently a victim of crosstalk, and an average of 43% of observations was corrected, resulting in an average exposure reduction of 38%. GSM 1800 downlink and UMTS uplink were less often corrected (6.9% and 8.9%), resulting in minor reductions in exposure (7.1% and 0.92%). The contribution of DECT to total RF‐EMF exposure is typically already low (3.2%), but is further reduced after correction (3.0%). Crosstalk corrections reduced the total exposure by 1.0% on average. Some individuals had a larger reduction of up to 16%. The code developed to make the corrections is provided for free as an R function which is easily applied to any time series of EMF measurements.

Conflicts of interest: Authors Jürg Fröhlich and Marco Zahner declare that they are involved in the company “Fields at Work,” which manufactures the ExpoM‐RF.

The extensive use of mobile phones worldwide has raised increasing concerns about the effects of electromagnetic radiation (EMR) on the brain due to the proximity of the mobile phone to the head and the appearance of several adverse neurological effects after mobile phone use. It has been hypothesized that the EMR-induced neurological effects may be mediated by amino acid neurotransmitters. Thus, the present study investigated the effect of EMR (frequency 1800 MHz, specific absorption rate 0.843 W/kg, power density 0.02 mW/cm2, modulated at 217 Hz) on the concentrations of amino acid neurotransmitters (glutamic acid, aspartic acid, gamma aminobutyric acid, glycine, taurine, and the amide glutamine) in the hippocampus, striatum, and hypothalamus of juvenile and young adult rats. The juvenile and young adult animals were each divided into two groups: control rats and rats exposed to EMR 1 h daily for 1, 2, and 4 months. A subgroup of rats were exposed daily to EMR for 4 months and then left without exposure for 1 month to study the recovery from EMR exposure. Amino acid neurotransmitters were measured in the hippocampus, striatum, and hypothalamus using high-performance liquid chromatography. Exposure to EMR induced significant changes in amino acid neurotransmitters in the studied brain areas of juvenile and young adult rats, being more prominent in juvenile animals. It could be concluded that the alterations in amino acid neurotransmitters induced by EMR exposure of juvenile and young adult rats may underlie many of the neurological effects reported after EMR exposure including cognitive and memory impairment and sleep disorders. Some of these effects may persist for some time after stopping exposure.

Exposure to electromagnetic radiation (EMR) is rapidly increasing in everyday environment, consequently conferring potential health effects. Oxidative stress is emerging as a mechanism implicated in pathophysiology and progression of various diseases. To our knowledge, no report has been made on the status of antioxidant redox systems after continuous exposure to radiofrequency radiation emitted from a Wi-Fi access point in animal model so far. Therefore, we aimed to continuously subject rats in the experimental group to radiofrequency (RF) radiation emitted from a commercially available Wi-Fi device. Male Wister rats were exposed to 2.45 GHz RF radiation emitted from a Wi-Fi for 24 h/day for 10 consecutive weeks. In order to assess the change in antioxidant redox system of plasma after continuous exposure to a Wi-Fi device, the total antioxidant capacity of plasma, level of thiobarbituric acid reactive substances, concentration of reduced glutathione (GSH), and activity of different enzymatic antioxidants, e.g., superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GSH-Px], and glutathione S-transferase [GST], were measured. In the Wi-Fi exposed group, a significant decrease was detected in total antioxidant capacity of plasma and the activities of several antioxidant enzymes, including CAT, GSH-Px, and SOD (P < 0.05). Meanwhile, the GST activity was significantly increased in this group (P < 0.05). However, no significant changes were found in GSH and TBARS levels following exposure to RF radiation. According to the results, oxidative defense system in rats exposed to Wi-Fi signal was significantly affected compared to the control group. Further studies are needed to better understand the possible biological mechanisms of EMR emitted from Wi-Fi device and relevant outcomes.

According to the results of the current research, long-term exposure to EMR emitted from wireless devices had adverse effects on the antioxidant potential of blood. Therefore, to protect individuals from harmful effects of Wi-Fi signals, it is advised to limit the use of such devices for household and occupational activities, if possible. This study may stimulate future helpful research in the development of new protective or therapeutic approaches. In addition, it is recommended that the target tissues of EMR emitted from wireless devices and the level of other mediators be investigated to understand the exact molecular mechanism and site of action upon continuous exposure to such radiations.

Modern technology has largely developed using energy forms of which the most relevant is surely electricity. Electric power stations generate alternate current at frequencies of 50 or 60 Hz, transmitted across high voltage transmission lines that are often located too near to buildings where humans live or work. In addition, home devices that work using alternate current expose humans to extremely low-frequency electromagnetic fields. Furthermore, trams, electric trains, and some industrial processes generate static magnetic fields. Electromagnetic fields produce non-ionizing radiation, which gives rise to the so-called electromagnetic waves pollution, also named electrosmog. A large scientific production study showed harmful effects of exposure to EMFs. In view of these results, the International Commission on Non-Ionizing Radiation Protection published international guidelines in order to recommend exposure limits to EMFs for occupational exposure and for general public exposure. The aim of this thematic issue is to give a further contribution to highlight the problem of electromagnetic waves pollution and to investigate the effects of exposure to EMFs on biological systems even below the EMF limits recommended by ICNIRP.

Conclusion

In conclusion, the studies reported in this thematic issue give further proof of significant effects in cellular functions induced by exposure to intensity levels of ELF-EMFs to which humans are generally exposed. Since it cannot be ruled out that such measured alterations can induce the onset of diseases in humans, it would be advisable to design shielding protection against exposure to EMFs or to plan electromagnetic systems and devices working at frequencies far from natural resonant frequencies of biological systems. These frequencies would be discovered in future research.

Objectives: We conducted a systematic literature review to identify studies fulfilling good scientific epidemiological standards for use in meta-analyses of occupational risk factors for amyotrophic lateral sclerosis (ALS).

Methods: We identified 79 original publications on associations between work and ALS. The MOOSE (Meta-analysis Of Observational Studies in Epidemiology) and GRADE (Grading of Recommendations, Assessment, Development and Evaluations) guidelines were used to ensure high scientific quality, and reliable protocols were applied to classify the articles. Thirty-seven articles fulfilled good scientific standards, while 42 were methodologically deficient and thus were excluded from our meta-analyses.

Results: The weighted relative risks for the various occupational exposures were respectively; 1.29 (95% confidence interval (CI): 0.97⁻1.72; six articles) for heavy physical work, 3.98 (95% CI: 2.04⁻7.77; three articles) for professional sports, 1.45 (95% CI: 1.07⁻1.96; six articles) for metals, 1.19 (95% CI: 1.07⁻1.33; 10 articles) for chemicals, 1.18 (95% CI: 1.07⁻1.31; 16 articles) for electromagnetic fields or working with electricity, and 1.18 (95% CI: 1.05⁻1.34; four articles) for working as a nurse or physician.Conclusions: Meta-analyses based only on epidemiologic publications of good scientific quality show that the risk of ALS is statistically significantly elevated for occupational exposures to excessive physical work, chemicals (especially pesticides), metals (especially lead), and possibly also to electromagnetic fields and health care work. These results are not explained by publication bias.

OBJECTIVES: We observed the efficacy of melatonin in preventing ovarian tissue damage in rats exposed to magnetic fields.

MATERIALS AND METHODS: Forty rats were divided into four treatment groups: Group 1, control group (n = 10); Group 2, melatonin administration only (n = 10); Group 3, magnetic field exposure only (n = 10); Group 4, magnetic field exposure with melatonin administration (n = 10). The magnetic field was applied at a dose of 20 μT for 30 min/day for 10 days. Melatonin was orally administered at a dose of 10 mg/kg. We evaluated follicle count, degree of fibrosis, amount of adhesion, amount of apoptosis, ovarian dimensions, and follicular degeneration by dissecting the ovaries of the rats on day 11, and differences among the groups were evaluated.

RESULTS: Group 3 had an increased amount of follicle degeneration, more fibrosis, and more adhesion than Group 4, but these findings were not statistically significant. The apoptosis scores in Groups 1 and 2 were significantly lower than in the other groups. Ovarian dimensions were significantly decreased in Group 3. Follicular degeneration was significantly increased in Group 3.

CONCLUSION: Exogenously administered melatonin, if used at much higher doses orally, may be a noncytotoxic, antiapoptotic agent and may also have a protective effect on ovarian tissue damage that radiation can cause at the level of fine structure

The study aimed to determine effect of extremely low frequency (50 Hz) electromagnetic fields (ELF-EMFs) exposure on serum levels of interleukin-17 (IL-17) and transforming growth factor-β (TGF-β) as signature cytokines of Th17 and regulatory T (Treg) cells, respectively. Retinoid-related orphan receptor γT and transcription factor forkhead box P3 (Foxp3) expression levels as lineage defining of Th17 and Treg cells were also assessed in the spleen and thymus. Eighty male rats were separated into 4 exposed groups (1, 100, 500, and 2,000 μT magnetic flux intensities) and a control. All rats were immunized by human serum albumin after 1 month of the exposure and the experiment was continued in the same manner for 1 month more. The results demonstrated that the weight of thymuses was significantly declined at intensity of 2,000 μT. At the preimmunization phase, the serum levels of IL-17 and TGF-β were significantly decreased at intensities of 1 and 100 μT. The expression of Foxp3 was also downregulated at intensities of 1 and 100 μT. In conclusion, low intensities of ELF-EMF may reduce the serum levels of IL-17 and TGF-β and downregulate the expression of Foxp3 in spleen.